Acetaminophen is a well known analgesic and antipyretic which reduces the discomfort and fever due to colds and other viral infections.
Pseudoephedrine and pharmaceutically acceptable salts thereof, e.g. the sulfate and the hydrochloride, are well known decongestants which restore freer breathing by shrinking nasal passages and promote sinus drainage in those suffering from colds, allergies or sinusitis.
Dexbrompheniramine and pharmaceutically acceptable salts thereof, e.g. the maleate, are well known antihistamines which provide relief of the pruritis, rhinitis and sneezing associated with colds and allergies.
Controlled release dosage forms are well known, including matrix tablet systems incorporating active ingredients, lubricants, binders, fillers and other excipients, wherein the binders may be hydrophillic, hydrophobic or water insoluble polymers. See for example U.S. Pat. No. 4,389,393. However, controlled release dosage forms which combine two actives are not common, and no controlled release dosage forms combining three actives in a single uniform dosage form are known. The mechanism by which controlled release dosage forms act to dispense the active ingredients over a period of time hve been described at length in the literature. See for example Manford Robinson, Chapter 14, "Sustained Action Dosage Forms", The Theory and Practice of Industrial Pharmacy, 2nd. ed., ed. L. Lachman, H. Lieberman and J. Kanig (Philadelphia; Lea & Febiger, 1976).